1. Field of the Invention
The present invention relates to a thin-film magnetic head to be incorporated into a magnetic disk unit.
2. Description of the Prior Art
Shown in FIGS. 3 and 4 is a conventional thin-film magnetic head 1 of a two-element type for recording and reproducing operation in combination with a hard disk. The thin-film magnetic head 1 comprises a floating slider 2, and two thin-film magnetic head elements 3A and 3B, which are denoted inclusively by a reference numeral "3", formed on the end surface of the floating slider 2. A lower magnetic film 4, a nonmagnetic film 5 for forming a magnetic gap g, an insulating film 6 and a conductive film 3, ordinarily, a copper film, for forming a coil are formed sequentially in that order on the end surface 2a of the floating slider 2, an opening is formed so as to face the rear connecting portion of the lower magnetic film 4, an upper magnetic film 8 is formed so as to be connected to the lower magnetic film 4 through the opening and so as to form the magnetic gap g between the lower magnetic film 4 and the upper magnetic film 8 with the magnetic film 5 therebetween, terminals 7a and 7b to be connected to lead wires are formed in the conductive film 7, and then a protective film 9 is formed to complete the thin-film magnetic head elements 3A and 3B.
Generally, the terminals 7a and 7b of the conductive film 7, and the thin-film magnetic head elements 3A and 3B are formed on the same end surface 2a of the floating slider 2 as proposed in, for example, Japanese Patent Laid-open (Kokai) No. 57-105819.
The terminals 7a and 7b of the thin-film magnetic head 1 occupy a large area in the end surface 2a of the floating slider 2. To reduce the effect of external vibrations on the thin-film magnetic head 1 by reducing the size and weight of the thin-film magnetic head 1, efforts have been made to reduce the size of the floating slider 2 through the curtailment of the area occupied by the terminals 7a and 7b. A current millislider is 3.2 mm in width, 4.0 to 4.7 mm in length and 0.86 to 1.27 mm in height. A microslider of 2.1 to 2.3 mm in width, 2.5 to 2.9 mm in length and 0.50 to 0.86 mm in height, and a nanoslider of 1.6 mm in width, 2.0 mm in length and 0.4 to 0.5 mm in height have been developed. Further efforts are being made to develop a picoslider smaller than such a nanoslider. However, the reduction of the size and weight of the thin-film magnetic head has been limited by the limit of reduction of the terminals 7a and 7b.
The terminals 7a and 7b are formed by selective plating, and then the protective film 9 is formed by sputtering a protective material, such as Al.sub.2 O.sub.3. During the sputtering process for forming the protective film 9, Al.sub.2 O.sub.3 is deposited also over the terminals 7a and 7b, and hence portions of the protective film covering the terminals 7a and 7b must be removed by a film removing means, such as lapping. Accordingly, portions of the conductive film, i.e., the copper film, forming the terminals 7a and 7b must be formed in a thickness greater than the distance between the surface of the insulating film 6 on which the conductive film 7 is formed and the upper surface of the upper magnetic film 8, which requires much time and labor which cannot be disregarded and requires complicated manufacturing processes.